Steel mill conveyer for heated material



July 4, 1939. J. E. M BRIDE STEEL HILL CONVEYER FOR HEATED MATERIAL H e1 ..d x m H W 2 m a n m L L W\ k\ m 0 .r A M. n N x E H 5 .YA m I I I IJ 2 1. m l s I k m 8 Q Q 9 MW 1 8 l h C r a M d e 1 i F .1. E. McBRIDE2,164,535

MILL CONVEYER FOR HEATED MATERIAL July 4, 1939.

STEEL Filed March 18, 1958 2 Sheets-Sheet 2 /Z 3/ n a INVENTOR. Jesse E.Me firm e ATTORNEY Patented July 4, 1939 UNITED STATES PATENT OFFICE-STEEL MILL CONVEYER FOR HEATED MATERIAL Jesse B. McBride, Highland Park,Mich., assignor to Palmer-Bee Company, Detroit, Mich., a corporation ofMichigan This invention relates to a hot slab transfer conveyerparticularly adapted, by relative arrangement and design of its severalparts, for use in steel mills for transferring heavy heated materialsuch ashot slabs of steel from heating furnaces as well as to and fromother operations. v

In modern steel mills heavy slabs of the material, which varyconsiderably in size, are heated in a furnace in preparation for forminginto desired shapes in a rolling mill. It is a necessary part of theseveral stages in the process that the slabs be transferred while in aheated condition. Previous to the last few years the distance which thehot slabs were required to be transferred was not greater than thirty tofifty feet and at no time were the slabs intended to be cooled on theconveyer. In this case it was practical, because of the short length ofthe conveyer, to use socalled track chains with pusher dogs projectingtherefrom which pushed the slabs over steel or castiron grids. However,in the present day rolling mills the distance over which the slabs aretransferred has been greatly increased and the length often reaches 100or 200 feet. This increase in length is necessary because of theenlargement of the mills and because it has become important that theslabs be cooled during transfer on the conveyer, thereby resulting in acontinuous operation eliminating unnecessary transfer on and off theconveyer. Since the 30 to 50 foot length conveyer was about the maximumpractical length over which a great number of slabs could be pushed bytrack chains it is necessary to use some new method to eliminatefriction if the length of the transfer is to be increased to 100 or 200feet. Although a conveyer of such length is easily constructed in anordinary installation, much more difficult problems arise when attemptis made to construct a unit capable of carrying large slabs of heatedsteel. In the type of conveyer previously used the support problem wassolved by the use of grids which could of course be designed foradequate support, but with the increased length now required it would beimpractical to slide or push the slabs on grids because of the greatly.

increased frictional load which would be thrown on any pusher unitcalled upon to slide the plurality of slabs extending over the fulllength of the conveyer. Furthermore, since the conveyer is now generallymade use of as a cooling bed, the problems arising from the considerabletransfer of heat to adjacent parts of whatever conveyer unit is usedmust be seriously considered,

the most important problem in this connection being elimination offriction and the protection of the anti-friction bearings from injury byheat.

It is therefore a primary object of the present invention to provide aconveyer construction particularly adapted for transfer of hot slabs ofsteel over long distances, the several parts of said conveyerinstallation being so positioned relative to each other as to effecttransfer of the heated material with a minimum of frictional resistancein the conveyor system while providing a position for anti-frictionbearings or other rotating units such that they will be adequatelyprotected from excessive transfer of heat.

It is a further object to provide a conveyer for transporting hot slabsof material with a plurality of chains positioned in parallelrelationship and spaced in such manner as to allow various lengths ofslabs to be carried crosswise of said chains.

It is another object to provide adequate support for a chain conveyer bysupporting said chain on a plurality of large diameter rotating parts sothat the chain which supports the heated material to be carried isdisplaced a sufficient distance from anti-friction bearings forsupporting said large diameter rotating parts so that heat insulatingmembers may be placed between the outer circumference of said parts andsaid bearings.

The above and other objects of the invention will appear more fully fromthefollowing more detailed description and by reference to the followingdrawings forming a part hereof and wherein:

Fig. 1 shows a side view of one end of the conveyer indicating theposition of the conveyer chain, a driving sprocket, supporting rolls andbearings therefor and heat insulating means therefor.

Fig. 2 shows a cross section through the con-' veyer unit takensubstantially on the line 22 of Fig. 1, showing the arrangement of thelarge diameter carrying rolls and the smaller return rolls and also thearrangement for carrying long or short slabs of the material.

Fig. 3 is a detailed view of one of the large diameter carrying rollsand the return rolls indicating the method of support for the bearingsand the insulating means employed.

Fig. 4 is a top view of the same portion of the conveyer as is shown inthe side view of Fig. 1.

Referring to the drawings, Fig. 1 shows one end of a conveyer run with asection of the conveyer which carries the slabs of material, and a heavyblock type chain I0, preferably made of alloy steel and heat treated,smooth on both top and bottom. The chain I is made of extra heavysection to withstand the shock of steel slabs which are pushed onto thechain at the receiving end. this heavy construction being also necessaryto properly withstand the excessive temperatures to which the chain isnecessarily subjected. As shown in Fig. 1, the chain is driven aroundthe sprocket II and a similar sprocket at the other end of the linewhich is not shown. Adequate support for the heavy loads to be carriedis assured by the use-of a plurality of closely spaced relatively largediameter rolls I2 which are mounted on shafts I3 and provided withbearing blocks I4 at their ends. These bearing blocks are supported onlongitudinally extending structural members I5 here shown as I-beamsections, the bearing blocks I4 being mounted on the top of the I-beam,as shown best in Fig. 2. The rolls I2 with suitable supporting bearingsare distributed along the path of the chain and are relatively closetogether, as shown in Fig. 1, in order to adequately support the chainand its load of heated material. The rolls I2 are also provided withflanges I6 to properly guide the chain II! in its path.

As shown in Fig. 2, several parallel strands of chain are used, eachwith the previously described distribution of supporting rolls so thatvarious lengths of slab material may be carried crosswise of the chainstrands. There are six chain strands shown in Fig. 2 indicated as I0,Ina, IIlb, I00, Illd and IIle. It is noted that the strands II'I, Illa,lb and- H are relatively close together while the spacing of the 'unitsI00, "id and We are at a greater distance apart. This lateraldistribution and number of supporting chain strands can be arranged asdesired so that short lengths can,

for instance, be supported across the chains I0, Illa and Iilb, whilemuch longer lengths can be carried to extend to the right over thechains IIlc, IM and Iile. The use of common shafts I3, each supportingtwo rolls for a pair of chain strands, is considered advisable for heavyload as it places a bearing closely adjacent the roll which supports thechain, although it might be permissible in some installations to use oneshaft to support more than two rolls.

Each of the chains I0 is supported on return rolls H which are mountedon shafts I8 below the rolls I2. These rolls II are of smaller diameterthan the rolls I2 and serve to support the chain in its return run. Theshafts I8 are supported by bearing blocks I 9 which are mounted on thebottom side of the I-beam section I5. The lower return run of the chainis allowed to sag between the supporting rolls I'I, this excess lengthof chain being made use of to take care of expansion and contraction ofthe chain due to variation in temperature. This feature is of greatimportance in a conveyer which is used to carry heated material.

Referring to Figs. 2 and 3 it is noted that the diameter of the rolls I2is such as to place the chain I0 in a position considerably above thecenter of the shafts I3 on which the rolls are mounted. This serves toposition the chain and the hot slabs of steel a considerable distancefrom the bearings and thereby helps to minimize the heat transfer fromthe slabs to the bearings. However, to further protect the bearings fromexcessive heat an insulating means is used in the form of twolongitudinal channels 20 and 2I mounted as shown in Fig. 3 in aninverted position with spacers 22 secured therebetween. This assembly ofspaced channel members is supported a distance above the bearing blocksI4 and below the chain III by vertical members mounted between eachshaft I3 on the top of the I-beam section I 5. It is apparent that theprovision of two channels with an air space between provides aneffective insulation of the bearings from the hot slabs carried on thetop of the chain I0. It is noted that the position of the channels 20and 2| is between the top of the rolls I2 and the center of the shaft I3and that these channels are of such width as to extend over the bearingblocks I4 on each side.

As shown at 24 in Fig. 3 the bearings used in each of the bearing blocksI4 are self-aligning roller bearings and are used both to cut down thefriction load and to permit the shafts to turn freely in their supportseven if they should be warped by heat or misaligned by other means.

When the several parts of the conveyer are positioned as above describedwith several strands of conveyer chain placed in a parallel relationshipover the entire length of the proposed travel of the conveyer, thesupported top strands of the chain form a transporting base for largearticles such as heated slabs of steel, the parallel strands of chainbeing so spaced as to make a supporting platform for various lengths ofmaterial which may be placed crosswise on top of these moving chainstrands. Such a plurality of strands is shown in Fig. 2. The use of aplurality of large diameter rolls I2 spaced relatively close togetherprovides in effect a rolling support on which each chain travels, theflanged construction of the rolls providing an adequate guide for eachchain. Furthermore, the use of the large diameter rolls with thebearings at the center and to one side of the chain strands affords allthe advantages of an anti-friction bearing supported unit withoutplacing the bearings in close proximity to the load to be carried whichin this case is intended to be of material which will give off aconsiderable amount of heat.

Another important feature is the particular construction and arrangementof the parts which makes possible the use of a longitudinal insulatingmember which covers the several bearings and is positioned between theheated load and the bearings, thus further deflecting the heat. Thisunit is preferably constructed of at least two sections of structuralsteel or other suitable material spaced apart as shown in Figs. 2 and 3of, the drawings.

It is apparent that the construction of the conveyer unit isparticularly adapted for the carrying of heavy heated loads with the useof parts which are of sufiicient size to withstand the loads to whichthey are necessarily subjected and still afford a construction which isexceptionally free from friction, so that the longer length of conveyertravel which is now required in steel mills may be accomplished withoutthe use of a plurality of units or the use of excessive power.

In addition to the special features of construction which protect theanti-friction bearings from excessive heat the conveyer is furtheradapted for carrying heated loads by a novel arrangement of the supportsfor the chain. As shown in Figs, 1, 2 and 3, the lower return run ofeach chain has a plurality of supporting rolls H, the spacing of therolls I! being materially greater than that of the load supporting rollsI2 so that the chain is allowed to sag between the several rolls and bythis means compensates for changes in length of the chain produced byvariations in temperature. This result is accomplished by such aconstruction since the load supporting upper rolls l2 are spaced closetogether and the chain is therefore not allowed to sag between supports.However, on the lower run the wide spacing of rolls H allows the chainto sag and the variation in length is therefore compensated in thissection, the chain quickly adjusting itself in all sections because ofits continuous movement.

10 Although I have described my invention as applied to a particularconstruction selected for the purposes of illustration, it is understoodthat various modifications may be resorted to and I therefore do notdesire to limit myself to the 15 particular construction hereindisclosed but rather to the scope of the following claims.

I claim:

1. In a conveyer for transporting heavy heated material, parallel chainstrands for supporting said material, a plurality of relatively largediameter rolls distributed to support said chain,

strands, bearings for supporting said rolls positioned at the side ofsaid chain strands, and heat insulating members mounted longitudinallyand above said bearings but below the outer circumference of said rolls.

2. In a conveyer for transporting relatively heavy heated loads,parallel chain strands adapted for supporting said load, ananti-friction support for said chain strands and load comprising aplurality of spaced rolls, bearings supporting said rolls for rotationbeneath said chain for support thereof, said bearings positioned adistance below and to each side of said chain allowed by a relativelylarge diameter of said rolls whereby transfer of heat to said bearingsis minimized, longitudinal members covering said bearings and positionedbelow said chain and above said bearings whereby said bearings arefurther insulated from transfer of heat from said lead.

3. In a conveyer for conveying and cooling hot slabs of heated material,parallel strands of chain for supporting said slabs, rolls forsupporting the heavy load of said chain and said slabs spaced beneathsaid chain, shafts for mounting said rolls for rotation having endsprojecting outport for said chain strands and load comprising aplurality of spaced rolls, bearings supporting said rolls for rotationunder said chain, said bearings positioned at a distance below saidchain allowed by a relatively large diameter of said rolls wherebytransfer of heat to said bearings is minimized, a plurality of spacedsuperimposed longitudinal members covering said bearings and positionedbelow said chain and above said bearings whereby said bearings arefurther insulated from transfer of heat from said load.

5 In a conveyer for transporting heavy slabs of heated material,parallel strands of chains for supporting said slabs, rolls forsupporting the heavy load of said chains and said slabs spaced beneathsaid parallel chain strands, shafts for mounting said rolls forrotation, having ends DI'O'.

jecting outwardly from said parallel chain.

strands, self-aligning bearings for said shafts positioned on saidprojecting portions, supports for said bearings, heat deflecting andinsulating members covering said bearings and positioned below saidchain strands and above said bearings, said rolls being of such diameteras to provide sufllcient distance between said chain and said bearingsas to allow for the mounting of said heat insulating members wherebyupon co: operative action of said self-aligning bearings and heatdeflecting members said chain is mounted for operation with aminimum offriction while carrying a heavy load of heated material regardless ofthe heat transmitted from said heated material.

* JESSE E. McBRIDE.

